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**vngx-jsch** (beta) is an updated version of the popular JSch SSH library
written in pure Java. It has been updated to Java 6 with all the latest
language features and improved code clarity.
/*
* Copyright (c) 2002-2010 Atsuhiko Yamanaka, JCraft,Inc. All rights reserved.
* Copyright (c) 2010-2011 Michael Laudati, N1 Concepts LLC.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The names of the authors may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
* INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.vngx.jsch;
/**
* Implementation of Request for sending requests to set/update
* environment variables.
*
* Environment variables may be passed to the shell/command to be started
* later. Uncontrolled setting of environment variables in a privileged process
* can be a security hazard. It is recommended that implementations either
* maintain a list of allowable variable names or only set environment variables
* after the server process has dropped sufficient privileges.
*
*
*
* @author Atsuhiko Yamanaka
* @author Michael Laudati
*/
final class RequestEnv extends Request {
/** Constant name for environment variable request. */
static final String ENV_REQUEST = "env";
/** Environment variable name to set (byte[] instead of String to support different encodings). */
private byte[] _name = new byte[0];
/** Environment variable value to set (byte[] instead of String to support different encodings). */
private byte[] _value = new byte[0];
/**
* Sets the environment variable name and value to send in request. The use
* of byte[] instead of String is to allow for any character encoding.
*
* @param name of environment variable
* @param value of environment variable
*/
void setEnv(byte[] name, byte[] value) {
_name = name;
_value = value;
}
/**
* Sends a request to update the environment variable.
*
* {@inheritDoc}
*
* @param session
* @param channel
* @throws Exception
*/
@Override
void request(Session session, Channel channel) throws Exception {
super.request(session, channel);
// byte SSH_MSG_CHANNEL_REQUEST(98)
// uint32 recipient channel
// string request type // "env"
// boolean want reply // 0
// string env name // environment variable name
// string env value // environment variable value
Buffer buffer = new Buffer(200 + _name.length + _value.length);
Packet packet = new Packet(buffer);
packet.reset();
buffer.putByte(SSH_MSG_CHANNEL_REQUEST);
buffer.putInt(channel.getRecipient());
buffer.putString(ENV_REQUEST);
buffer.putBoolean(waitForReply());
buffer.putString(_name);
buffer.putString(_value);
write(packet);
}
}